feat: add PoC of Subscribe API

[weboko]

Problem / Description

Solution

Notes

• Resolves
• Related to

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Checklist

• Code changes are covered by unit tests.
• Code changes are covered by e2e tests, if applicable.
• Dogfooding has been performed, if feasible.
• A test version has been published, if required.
• All CI checks pass successfully.

[github-actions]

size-limit report 📦

Path	Size	Loading time (3g)	Running time (snapdragon)	Total time
Waku node	97.51 KB (+1.47% 🔺)	2 s (+1.47% 🔺)	1.7 s (-9.38% 🔽)	3.7 s
Waku Simple Light Node	148.64 KB (+0.86% 🔺)	3 s (+0.86% 🔺)	1.8 s (-2.16% 🔽)	4.8 s
ECIES encryption	22.56 KB (+0.25% 🔺)	452 ms (+0.25% 🔺)	380 ms (-12.07% 🔽)	831 ms
Symmetric encryption	22 KB (+0.4% 🔺)	440 ms (+0.4% 🔺)	361 ms (-31.87% 🔽)	801 ms
DNS discovery	52.11 KB (-0.08% 🔽)	1.1 s (-0.08% 🔽)	1.4 s (+57.99% 🔺)	2.5 s
Peer Exchange discovery	52.83 KB (-0.15% 🔽)	1.1 s (-0.15% 🔽)	1.6 s (+100.34% 🔺)	2.6 s
Peer Cache Discovery	46.58 KB (+0.02% 🔺)	932 ms (+0.02% 🔺)	1.1 s (+65.65% 🔺)	2 s
Privacy preserving protocols	77.14 KB (+0.11% 🔺)	1.6 s (+0.11% 🔺)	2.2 s (-1.37% 🔽)	3.7 s
Waku Filter	79.68 KB (-0.02% 🔽)	1.6 s (-0.02% 🔽)	1.6 s (+2.46% 🔺)	3.2 s
Waku LightPush	77.92 KB (+0.2% 🔺)	1.6 s (+0.2% 🔺)	1.8 s (+10.93% 🔺)	3.4 s
History retrieval protocols	83.56 KB (-0.06% 🔽)	1.7 s (-0.06% 🔽)	1.4 s (-27.02% 🔽)	3.1 s
Deterministic Message Hashing	28.89 KB (-0.05% 🔽)	578 ms (-0.05% 🔽)	737 ms (+35.26% 🔺)	1.4 s